【英语】定语从句题的疑问

题目

【英语】定语从句题的疑问
wind power is an ancient source of energy_______ we may return in the near future.
A on which B by which C to which D from which
为什么选c不选D?顺便分析下句子结构
.
:“I‘d like to give my thanks to those _____ help my son will be able to survive his terrible disase"
A who B that C with whose D with their
为什么选c 不选A?

答案

return to the wind power 就是说不久的将来我们可能又会回过头去使用风能这种能源.

return from 的意思是从...回去,你想未来到从前,那肯定是回到从前不是从从前回去.
如果你选A那后面先不看意思“who help my son will be able to survive his terrible disase”
直接就是一句话了（who help my son主语 will be able to 谓语,虽然没有意义）
为方便理解的话你可以把前面的those改成the people,我想感谢那些人,什么人呢,给我儿子度过疾病帮助的人.with the help of those people,my son 才能够survive